Temperature-indicating device



R. G. LAFlTE TEMPERATURE INDICATING DEVICE Jan. 3, 1928.

Filed Feb. 5, 1925 lllllll l ATToRN EY Patented Jan. 3, 1928.

noenne. tantra, or LIBERTY, MISSOURI.

TEMPERATUREJNDIC A TING DEVICE.

Application filed February My invention relates to a temperature indicating device for motor vehicles and more particularly to one of that type wherein a thermometencombined with a radiator cap, is assembled with the radiator of a motor vehicle engine in a manner to efiiciently and accurately indicate condition of a cooling medium in circulation within the radiator and engine; the principal objects of the invention being to stabilize action of the indicator under varying conditions of the cooling medium, simplify the assembly of the indicating elements with the radiator cap, protect the indicating elements, and render the indication thereof readily visible by night as well as by day.

In accomplishing these objects I have provided improved details of structure, the preferred forms of which are illustratedin the accompanying drawings wherein:

Fig. 1 is an elevation of a device embodying my invention; s V

Fig. 2 is a central, vertical section of the same.

Fig. 3 is a central, horizontal section of the same. I 7

Fig.4 is a-detail perspective view of a reflector for the temperature indicating ele-. ment.

Fig. 5 is a reverse perspective view of the reflector. I

Referring more in detail to the drawings,

1 designates the ring element of a radiator cap which is threaded onto the neck 2 of the radiator of a motor vehicle and provided with an inturned flange 3 constituting a stop element foreng'agement with the top of the radiator neck. Seated on the flange 3 is a sealing ring 4 and rising from the inneredge of the flange is a shoulder 5, forming a throat above the flange and in turn oifset to form a collar 6, slottedat the rear to provide the ears 7for receiving the hinge lug 8 of'the cap head 9 and extended forwardly opposite the lug 7 to. form the walls 10 of a latch boX 11. lhe cap head 9 is provided with a depending, tapered ring 12 adapted toseat on the sealing ring at to form a closefjoint for preventing the escape ofcooling medium from the radiator either in the form of liquid, vapor or gas; the head ring being normallyheld securely to the sealing ring by a ball 13, pivotally mounted on the cap r ng 1 and adapted for seating in notches 1 1 in the 5, 1926. Serial 1V0. 86,182.

latch ear 15 that seats within the latch box 11.

The parts heretofore describedare not particularly novel and may be varied with different forms of caps to which my improvement may-be applied.

In a cap embodying my, improvements the top of the head 9 is flat, and extend'-;

ing into the head from the top to near the bottom of the head is an annular groove 16 and an interior socket 17, the, base of which latter is grooved as at 18 to form the center boss 19, the wall 20 located between the grooves 16 and 18 bein threaded at its inner face to the level ofthe boss 19 and there offset to form a shoulder 21 for seating the shank of the indicator element as hereinafter described; the grooves at opposite sides of the wall constituting air chambers for insulating the'interior of the head and thereby stabilizing temperatures within the cap, which are'subject to'variations under changing conditions in thecooling system.

The top of the boss19 is provided with a recess '22 for seating the hulb 23 of a thermometer'tube .24 constituting the variable indicating element of the device. The thermometer tube is housed in aframe comprising a ring '25 integral with a neck 26 flared outwardly and downwardly and provided with a flat under surface 27 adapted to seat on the flat top of the cap ring 9 and cover the orifices thereof, the bottom of the neck having a threaded shank 28 fitting within the-Wall 20 of the radiator cap ring and seating'on'the boss 19 and shoulder 21 to cover the annular groove 18; The neck 26 and shank 28 contain a central socket 29 concentric with the recess 22 in the top of the boss 19; and connecting the socket 29 with the interior of the ring 25 is a channel 30 registering with a "socket 31 within the ring, at the topthereof,

the thermometer tube extending up through the channel 30 and terminating within the socket 31. A spring 32 surroundingthe thermometer tube within the socket 29 bears against the base 33 of the socket 29 and against the bulb 23, serving to hold the bulb within its seat and prevent rattling of the tube in its guarding channel and tip socket, thereby stabilizing the tube and avoiding breakage thereof travel of'the vehicle.

under arr-ing The front face of the ring 25 is provided ring 37 extending beyond the inner edge of the groove 3a and overlying the bevelled edge 38 of a window glass 39, the keeper ring 37 being secured to the body ring by screws or the like 40 to remova-bly mount the glass so that the latter will be held securely in placebut afford access to the thermometer tube. The rear edge of the ring 25 is provided with grooves 41 and 42 corresponding to the grooves 34; and 35 at the frontof the ring, and seated in said grooves are keeper rings 43 and 44, corresponding to the rings 36 and 37, except that the inner keeper ring 43 is equipped with a reflector 4:5 for directing rays of light onto the thermometer tube from lamps on the vehicle to which the indicating device is applied, from a flash light carried by the driver of the vehicle, from street-lamps or from the headlights of other vehicles. I prefer to stamp the ring 43 from a single piece of sheet metal of a diameter tofit the groove 42 and cut interiorly to provide the vertical rails 46, spaced to a slightly greater extent than the width of the ther mometertu-beso that the latter maybe exposed therebetween, with spaces at the sides of the tube through which light rays may pass to contact 'with'the reflector. v

The reflector 45-, in my preferred form, constitutes extensions from the rails 4 6, which are bent forwardly to form wings 47', the forward edges of which contact with the front glass 39 to exclude light rays from the sides of the device and intercept rays from the rear of the device or from the front thereof that might enter through the spaces 48 and 4:9 The edges of the rails 46 maybe notched'as at 50, 51 a'n-d 52, and .pro-

'vided with indicia adjacent the notches to indicate certain conditions of the cooling system.

Operation of an indicating device constructed and assembled as described is as follows: p 7 v Y Assu-ming the device to be mounted on a motor vehicle in operation and with the cooling medium in circulation, the thermometer, being subject to variations in temperature of the cooling medium within the circulating system, will indicate the temperature of the medium by level of the indicating fluid within the thermometer tube. When an adequate supply of cooling medium is circulating in the system, level of the fluid will remain substantially constant, but if the supply of the medium is reduced so that the remaining volume is raised in temperature, the temperature of the cap head is varied proportionately, raising-the temperature of the air within the head grooves 16 and 18, and correspondingly varying the temperature of the fluid inthe thermometer tube, expanding the fluid and raising its level within the tube, the rise inrlevel of the fluid corresponding to rise in temperature of the cooling medium.

7 It is 'appar'ent that the thermometer elef tube, thereby enhancing 'serviceability of the dev ce.

What I claim and desire to secure by Letters Patent is p v 1. A device ofthe charactervdescribe'd including,.in combination with an attaching ring, a head hinged to the ring having an imperforate bottom, an upwardly facing socket, and a bulb seat with-inthe socket, a

frame having a recessed shank secured in said socket, and a thermometer having a bulb located in saidseat' and a 'tubeextended through the shank into said frame.

2. A device of thecharadter described in:

eluding, in combination with an attaching ring, ahead hinged to the ringhaving an imperforate bottom, an upwardly facing sooket -and a bulb seat within the socket,fa

frame having a recessed shank secured in said socket, a thermometer having a bu'l'bjlocated in said seat and a tube extended through the shank into said frame, and a spring in said shank retaining said bulb in its seat. v V

A device of the character described'im eluding, in combination with an attaching ring, a head hinged to the ring, having an imperforate bottomprovided with an up wardly facing bulb seat, a frame anchored to said head, having a tube channel and spring socket, a thermometer having its bulb located in said seat and i'tsftube extended through the frame socket and channel, and aspring in said socket surrounding the "tube and engaging the bulb to retain the bulb in its seat. V

4. In combination with a radiator neck, a cap comprising a ring member for attaching the cap to the neck, "a cover member hinged to the ring and normally closing the neck, the'cover member having a seat in its up-per 'face and having grooves concentric with and forming spaced walls about theseat, a'housi ng member having a shank fitted into the cover member over said seatand an opening exposed to said seat, and a thermometer having a bulb seated in said -seat 'and'a tube extending through said opening into said housing.

5. A temperature indicating device for motor vehicles comprlsing, in combination with a radiator neck, a closure for said neck comprising a cap engaged with the neck and having an outwardly opening socket, and a cupped boss Within the socket, a shank hav ing a socket opening to the boss cup, a ring mounted on said shank having a channel opening to the shank socket and having a recess opposite the channel, a thermometer comprising a bulb seated in the boss cup and a tube extending through said socket, through said channel and through the ring to anchorage in said recess, and a spring in the shank socket engaging the thermometer bulb to retain the latter in its seat.

6. A temperature indicating device of the character described, comprising in combination with a radiator neck, a ring on said on said boss and having a socket opening to the boss cup, a ring on said neck having an upper, inwardly opening recess and a channel registering with the recess and communicating with the neck socket, a thermometer comprising a bulb seated in the boss seat and a tube extending through the neck channel, through the interior of the ring and into said socket, and a spring in the neck socket bearing against the base of the socket and against the thermometer vbulb for the purpose set forth.

In testimony whereof I aflix my signature.

ROGER G. LAFITE. 

